. - how do you estimate the income on mid-term rentals?

Giving up $100k+,in tax free income.

That will give you income to invest.

With two rentals, you might consider QuickBooks Online Plus, which allows you to track income and expenses by class codes (ideal for separating each property’s income & expenses to assess profitability by property).

@Brenden Sperl - Can you clarify you rental income?

I have  a W2 job and look forward to the losses this year to offset some of my income (Not my 'WHY' for running an STR, but a nice bonus).

Estimated costs range from $500–$1,000 annually, depending on the complexity of their LLC and rental activity.For Partner 2 ($148K joint income, W-2, 1099 income, 1 rental, 2 kids), a CPA is strongly recommended.

Save that down payment money you mentioned or go for a multi family at a higher price than the single but have rental income. 

My overall goal is have passive income while I am able to travel the world at ease. 

Any brokerage can be the right fit for you so long as you commit to taking initiative and putting in the work.By 'work', I mean income-producing activities (lead generation and follow-up) i.e. cold calling, door-knocking, contacting your sphere of influence, networking, hosting open houses, running online advertising, marketing (paper or online), or anything else that will get you in front of prospective clients.My first broker rarely answered my phone calls and by the time she responded, I'd often already have the answer I was looking for.